Medical equipment only after regular irregular , in order to ensure the accuracy of medical measurements and the unity of the unit, the use of safety and effectiveness. Otherwise, the use of medical equipment without certainty or even measurement inaccuracy, error is too large, it is difficult to ensure the correctness of clinical diagnosis and treatment. Quality assurance and control of medical equipment permeates all aspects of medical equipment management, the accuracy of its measurement results is always a key issue in controlling the quality of equipment, and medical measurement is to ensure that medical equipment is accurate and reliable value of the important technical basis.